Federal, state and local officers secured hundreds of pieces of debris and special teams collected human remains at the end of the debris path in Nacogdoches and Sabine counties near the Louisiana state line.

"There have been some remains here and in some other of the counties but we don't want to go into any other further detail," Nacogdoches County Sheriff Thomas Kerss said, adding that he was acting out of respect to the families.

Remains were also found in Sabine County to the southeast of Nacogdoches, a town of about 32,000 that appeared to be where most of the debris rained down Saturday morning in the wake of the breakup over the Dallas area.

Kerss said FBI agents or U.S. Marshals were called to the scene of human remains. A temporary morgue was established at Hemphill, a small town in Sabine County.

About 1,200 debris sites have been identified in Nacogdoches County and efforts were being made to secure those sites until federal agents arrived, officials said.

"Nobody is picking up that material right now," said County Judge Sue Kennedy. "GPS (Global Position Satellite tracking) is being used to pinpoint each site and it will be a federal agency that will go out and pickup debris."

Ron Dittemore, manager of the NASA shuttle program, said he did not have a date for removal of the debris but a team of more than 100 NASA officials was in the field to carry out the recovery.

"We are doing that cautiously as we want to protect the public and the evidence," he said at a NASA briefing at the Johnson Space Center.

Dittemore said the NASA staging area would be at Barksdale Air Force Base near Shreveport, Louisiana, about 80 miles northeast of Nacogdoches.

Stephen F. Austin State University in Nacogdoches was helping set up the GPS tracking at each site for the NASA investigation.

Debris included a 7-foot piece of metal, circuit boards, spacesuit mission patches and an astronaut's helmet. The parts fell on the roofs of buildings and cars in Nacogdoches, causing minor damage, officials said.

James Couch of Norwood in San Augustine County found the helmet on his property.

"We found debris in the yard and on the roof, mostly pipe and pieces, and some type of metal alloy. And a helmet," he told The Dallas Morning News. "It's just a regular space helmet. It's intact. The only thing that's missing is the shield that goes on the front."

Residents placed American flags and crosses at some of the sites in memory of the fallen astronauts.

Manpower was a major concern with local officials trying to secure all the numerous sites. The importance of each finding was assessed to determine if it deserved a 24-hour watch.

Most residents followed instructions; they avoided touching the debris and called police. The debris could be toxic because of the toxicity of shuttle fuels. Removing a piece of crash debris is also a federal crime.

Some people touched debris, however, and later learned that it might be toxic. As a result about 70 people were checked out at hospitals in Nacogdoches, according to Judge Kennedy, although she stressed none of them was ill.

Sunday evening, Gov. Rick Perry ordered school administrators in a 93-county area of Texas to check school grounds for debris from the shuttle.

"Although we have reports from only one school that has shuttle debris, we want to make certain that our school children are safe," he said."This precautionary measure will ensure that school sites have been inspected. Federal officials have assured us that schools will be the top priority for debris removal."

Kennedy said earlier Sunday that schools in Nacogdoches County have been instructed to check their grounds for debris and hopefully get it removed before Monday classes.

NASA officials warned again Sunday that members of the public should not touch any of the shuttle debris because it might be toxic.

"Something that looks innocent could have become contaminated because of the event," said Dittemore.

NASA has asked local officials to notify it immediately if they find any debris that might be from the "control center" of Columbia. Some of the debris might not be found soon because of two large national forests in that area of deep east Texas.

"There are (pieces of) debris that we are not going to find soon," Kerss said. "It may be hunters or others who eventually find some debris."

Most of the reports were coming from Nacogdoches County because it is more populous than most of the other counties in the area. Debris was also being found in western Louisiana.

Sabine County Sheriff Tommy Mattox said his office has received calls of concern about debris falling into the Toledo Bend Reservoir, which is a source of water for the community. He said water officials assured him it was safe.

More than 25 calls an hour are being received in Nacogdoches county, which is only one of about 19 counties southeast of Dallas that have reported finding Columbia debris.

Many residents of north and east Texas saw or heard Columbia break apart about 8 a.m. CST Saturday at more than 200,000 feet. It was traveling at 18 times the speed of sound and was only 16 minutes from landing at the Kennedy Space Center in Florida.